Various types of handlers for maneuvering integrated circuit devices to a test site interfacing with a tester mechanism are known in the art and are commercially available. Such handlers vary in construction and design depending upon the type of integrated circuit to be handled, the desired speed of handling, etc. Handlers vary from manual and/or semiautomatic structures which provide basic input and output movement of devices to be tested across a test site, to sophisticated, essentially fully automated systems capable of communicating with a host computer. While less sophisticated apparatus are capable of handling a relatively limited number of devices per unit time, more sophisticated mechanisms are capable of a throughput significantly in excess of apparatus which were state-of-the-art only a few years ago.
Optimally, a handler mechanism should possess a sufficient speed of operation so as to be economical in use. Various handler structures have, therefore, sought to maximize throughput by use of a number of different approaches.
The approach employed has, to some degree, been dependent upon the type of integrated circuit device being handled. Various of such devices are known and utilized in commerce and industry. The particular application to which a device is put can vary widely.
A first type of device is known as a dual in-line package (DIP). Such a device has a platen-like main body portion which houses the integrated circuitry of the device. The main body portion of such devices are, typically, rectangular in shape, opposite edges of the main body portion carrying a plurality of elongated contacts substantially parallel to one another and generally perpendicular to a plane defined by the main body portion. Typically, rows of such contacts extending from opposite edges are flared slightly outwardly away from each other. A DIP, therefore, tends to take the form of a spider-like structure.
A second type of integrated circuit device known in the art is characterized as a small outline integrated circuit (SOIC). Such devices are quite similar in appearance to DIPS. They include a platen-like main body portion, often square in shape, which has a row of contacts extending from opposite edges thereof. While in the case of DIPS, the contacts are substantially straight, SOIC contacts typically have distal portions angled from the rest of the contacts so as to be disposed generally parallel to a plane defined by the main body portion of the device of which they are a part.
A final relevant type of integrated circuit device known in the prior art is characterized as a plastic leaded chip carrier (PLCC). A PLCC has contact pads rather than probes extending from a main body portion, the pads comprising an integral part of the shape thereof. The contacts are, typically, disposed about the periphery of the main body portion. In some cases, the device is "castled" by the presence of the contact pads.
Certainly, in the case of PLCCs, the contacts are rigid. As previously indicated, they form an integral part of the shape of the main body portion of the device of which they are a part. In the case of DIPs and SOICs, however, the contact probes also have some measure of rigidity.
Because of this measure of rigidity, some handlers have been enabled to use a rotary shuttle type singulator wherein a device is introduced into a station in the shuttle at one location and the shuttle rotated so that the contacts of the device will be brought into engagement with probes at a test site. Typically, the test site probes are of such a construction so that they will flex outwardly as the device passes therebetween.
Illustrative of a structure similar to that described above is that disclosed in U.S. Pat. No. 3,655,041 (Baker et al). In the Baker et al patent, however, the test site probes are mounted to a pair of arms, each arm being disposed for rotation about a pivot pin. Cam actuation effects engagement of the test site probes with the contacts of the device to be tested when a device is in position at the test site. The arms are rotated about their respective pivot pins to bring the probes into engagement with the contacts of the device.
U.S. Pat. No. 4,128,174 (Frisbie et al) is another prior art reference which illustrates the use of a rotary shuttle-type device having a plurality of stations disposed about the periphery thereof. As best seen in FIG. 2 of that reference, an integrated circuit device such as a DIP can be received within one of the stations and passed between a pair of probe rows at the test site. The resiliency of both the contacts and the probes allows the device to be tested to pass after the testing operation has been performed.
As seen in both of those patent references, however, the device to be tested is not positively held at the station in which it is received at the periphery of the rotary shuttle. Consequently, the device can become canted within the station, improperly positioned radially with respect to the shuttle, or misaligned in some other manner. As a result, a particular contact of the device may not be brought into engagement with the proper probe at the test site. Alternatively, even if a particular contact is brought into engagement with its proper probe, all contacts might not be brought into engagement with their respective probes at the same time.
It is to these problems and desirable features dictated by the prior art that the present invention is directed. It is a disc singulator device which positively holds a device to be tested in a desired orientation and at a particular, desired location with respect to the test site probes. As a result, more reliable testing can be effected.